drivers/sbus/char/openprom.c

   1 /*
   2  * Linux/SPARC PROM Configuration Driver
   3  * Copyright (C) 1996 Thomas K. Dyas (tdyas@noc.rutgers.edu)
   4  * Copyright (C) 1996 Eddie C. Dost  (ecd@skynet.be)
   5  *
   6  * This character device driver allows user programs to access the
   7  * PROM device tree. It is compatible with the SunOS /dev/openprom
   8  * driver and the NetBSD /dev/openprom driver. The SunOS eeprom
   9  * utility works without any modifications.
  10  *
  11  * The driver uses a minor number under the misc device major. The
  12  * file read/write mode determines the type of access to the PROM.
  13  * Interrupts are disabled whenever the driver calls into the PROM for
  14  * sanity's sake.
  15  */
  16
  17 /* This program is free software; you can redistribute it and/or
  18  * modify it under the terms of the GNU General Public License as
  19  * published by the Free Software Foundation; either version 2 of the
  20  * License, or (at your option) any later version.
  21  *
  22  * This program is distributed in the hope that it will be useful, but
  23  * WITHOUT ANY WARRANTY; without even the implied warranty of
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  25  * General Public License for more details.
  26  *
  27  * You should have received a copy of the GNU General Public License
  28  * along with this program; if not, write to the Free Software
  29  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  30  */
  31
  32 #include <linux/module.h>
  33 #include <linux/kernel.h>
  34 #include <linux/errno.h>
  35 #include <linux/slab.h>
  36 #include <linux/smp_lock.h>
  37 #include <linux/string.h>
  38 #include <linux/miscdevice.h>
  39 #include <linux/init.h>
  40 #include <linux/fs.h>
  41 #include <asm/oplib.h>
  42 #include <asm/prom.h>
  43 #include <asm/system.h>
  44 #include <asm/uaccess.h>
  45 #include <asm/openpromio.h>
  46 #ifdef CONFIG_PCI
  47 #include <linux/pci.h>
  48 #endif
  49
  50 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost  (ecd@skynet.be)");
  51 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
  52 MODULE_LICENSE("GPL");
  53 MODULE_VERSION("1.0");
  54
  55 /* Private data kept by the driver for each descriptor. */
  56 typedef struct openprom_private_data
  57 {
  58         struct device_node *current_node; /* Current node for SunOS ioctls. */
  59         struct device_node *lastnode; /* Last valid node used by BSD ioctls. */
  60 } DATA;
  61
  62 /* ID of the PROM node containing all of the EEPROM options. */
  63 static struct device_node *options_node;
  64
  65 /*
  66  * Copy an openpromio structure into kernel space from user space.
  67  * This routine does error checking to make sure that all memory
  68  * accesses are within bounds. A pointer to the allocated openpromio
  69  * structure will be placed in "*opp_p". Return value is the length
  70  * of the user supplied buffer.
  71  */
  72 static int copyin(struct openpromio __user *info, struct openpromio **opp_p)
  73 {
  74         unsigned int bufsize;
  75
  76         if (!info || !opp_p)
  77                 return -EFAULT;
  78
  79         if (get_user(bufsize, &info->oprom_size))
  80                 return -EFAULT;
  81
  82         if (bufsize == 0)
  83                 return -EINVAL;
  84
  85         /* If the bufsize is too large, just limit it.
  86          * Fix from Jason Rappleye.
  87          */
  88         if (bufsize > OPROMMAXPARAM)
  89                 bufsize = OPROMMAXPARAM;
  90
  91         if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
  92                 return -ENOMEM;
  93
  94         if (copy_from_user(&(*opp_p)->oprom_array,
  95                            &info->oprom_array, bufsize)) {
  96                 kfree(*opp_p);
  97                 return -EFAULT;
  98         }
  99         return bufsize;
 100 }
 101
 102 static int getstrings(struct openpromio __user *info, struct openpromio **opp_p)
 103 {
 104         int n, bufsize;
 105         char c;
 106
 107         if (!info || !opp_p)
 108                 return -EFAULT;
 109
 110         if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
 111                 return -ENOMEM;
 112
 113         (*opp_p)->oprom_size = 0;
 114
 115         n = bufsize = 0;
 116         while ((n < 2) && (bufsize < OPROMMAXPARAM)) {
 117                 if (get_user(c, &info->oprom_array[bufsize])) {
 118                         kfree(*opp_p);
 119                         return -EFAULT;
 120                 }
 121                 if (c == '\0')
 122                         n++;
 123                 (*opp_p)->oprom_array[bufsize++] = c;
 124         }
 125         if (!n) {
 126                 kfree(*opp_p);
 127                 return -EINVAL;
 128         }
 129         return bufsize;
 130 }
 131
 132 /*
 133  * Copy an openpromio structure in kernel space back to user space.
 134  */
 135 static int copyout(void __user *info, struct openpromio *opp, int len)
 136 {
 137         if (copy_to_user(info, opp, len))
 138                 return -EFAULT;
 139         return 0;
 140 }
 141
 142 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 143 {
 144         const void *pval;
 145         int len;
 146
 147         if (!dp ||
 148             !(pval = of_get_property(dp, op->oprom_array, &len)) ||
 149             len <= 0 || len > bufsize)
 150                 return copyout(argp, op, sizeof(int));
 151
 152         memcpy(op->oprom_array, pval, len);
 153         op->oprom_array[len] = '\0';
 154         op->oprom_size = len;
 155
 156         return copyout(argp, op, sizeof(int) + bufsize);
 157 }
 158
 159 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 160 {
 161         struct property *prop;
 162         int len;
 163
 164         if (!dp)
 165                 return copyout(argp, op, sizeof(int));
 166         if (op->oprom_array[0] == '\0') {
 167                 prop = dp->properties;
 168                 if (!prop)
 169                         return copyout(argp, op, sizeof(int));
 170                 len = strlen(prop->name);
 171         } else {
 172                 prop = of_find_property(dp, op->oprom_array, NULL);
 173
 174                 if (!prop ||
 175                     !prop->next ||
 176                     (len = strlen(prop->next->name)) + 1 > bufsize)
 177                         return copyout(argp, op, sizeof(int));
 178
 179                 prop = prop->next;
 180         }
 181
 182         memcpy(op->oprom_array, prop->name, len);
 183         op->oprom_array[len] = '\0';
 184         op->oprom_size = ++len;
 185
 186         return copyout(argp, op, sizeof(int) + bufsize);
 187 }
 188
 189 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
 190 {
 191         char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
 192         int len = op->oprom_array + bufsize - buf;
 193
 194         return of_set_property(options_node, op->oprom_array, buf, len);
 195 }
 196
 197 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 198 {
 199         phandle ph;
 200
 201         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 202
 203         if (bufsize < sizeof(phandle))
 204                 return -EINVAL;
 205
 206         ph = *((int *) op->oprom_array);
 207         if (ph) {
 208                 dp = of_find_node_by_phandle(ph);
 209                 if (!dp)
 210                         return -EINVAL;
 211
 212                 switch (cmd) {
 213                 case OPROMNEXT:
 214                         dp = dp->sibling;
 215                         break;
 216
 217                 case OPROMCHILD:
 218                         dp = dp->child;
 219                         break;
 220
 221                 case OPROMSETCUR:
 222                 default:
 223                         break;
 224                 };
 225         } else {
 226                 /* Sibling of node zero is the root node.  */
 227                 if (cmd != OPROMNEXT)
 228                         return -EINVAL;
 229
 230                 dp = of_find_node_by_path("/");
 231         }
 232
 233         ph = 0;
 234         if (dp)
 235                 ph = dp->node;
 236
 237         data->current_node = dp;
 238         *((int *) op->oprom_array) = ph;
 239         op->oprom_size = sizeof(phandle);
 240
 241         return copyout(argp, op, bufsize + sizeof(int));
 242 }
 243
 244 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 245 {
 246         int err = -EINVAL;
 247
 248         if (bufsize >= 2*sizeof(int)) {
 249 #ifdef CONFIG_PCI
 250                 struct pci_dev *pdev;
 251                 struct device_node *dp;
 252
 253                 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0],
 254                                       ((int *) op->oprom_array)[1]);
 255
 256                 dp = pci_device_to_OF_node(pdev);
 257                 data->current_node = dp;
 258                 *((int *)op->oprom_array) = dp->node;
 259                 op->oprom_size = sizeof(int);
 260                 err = copyout(argp, op, bufsize + sizeof(int));
 261
 262                 pci_dev_put(pdev);
 263 #endif
 264         }
 265
 266         return err;
 267 }
 268
 269 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 270 {
 271         phandle ph = 0;
 272
 273         dp = of_find_node_by_path(op->oprom_array);
 274         if (dp)
 275                 ph = dp->node;
 276         data->current_node = dp;
 277         *((int *)op->oprom_array) = ph;
 278         op->oprom_size = sizeof(int);
 279
 280         return copyout(argp, op, bufsize + sizeof(int));
 281 }
 282
 283 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
 284 {
 285         char *buf = saved_command_line;
 286         int len = strlen(buf);
 287
 288         if (len > bufsize)
 289                 return -EINVAL;
 290
 291         strcpy(op->oprom_array, buf);
 292         op->oprom_size = len;
 293
 294         return copyout(argp, op, bufsize + sizeof(int));
 295 }
 296
 297 /*
 298  *      SunOS and Solaris /dev/openprom ioctl calls.
 299  */
 300 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
 301                                 unsigned int cmd, unsigned long arg,
 302                                 struct device_node *dp)
 303 {
 304         DATA *data = file->private_data;
 305         struct openpromio *opp;
 306         int bufsize, error = 0;
 307         static int cnt;
 308         void __user *argp = (void __user *)arg;
 309
 310         if (cmd == OPROMSETOPT)
 311                 bufsize = getstrings(argp, &opp);
 312         else
 313                 bufsize = copyin(argp, &opp);
 314
 315         if (bufsize < 0)
 316                 return bufsize;
 317
 318         switch (cmd) {
 319         case OPROMGETOPT:
 320         case OPROMGETPROP:
 321                 error = opromgetprop(argp, dp, opp, bufsize);
 322                 break;
 323
 324         case OPROMNXTOPT:
 325         case OPROMNXTPROP:
 326                 error = opromnxtprop(argp, dp, opp, bufsize);
 327                 break;
 328
 329         case OPROMSETOPT:
 330         case OPROMSETOPT2:
 331                 error = opromsetopt(dp, opp, bufsize);
 332                 break;
 333
 334         case OPROMNEXT:
 335         case OPROMCHILD:
 336         case OPROMSETCUR:
 337                 error = opromnext(argp, cmd, dp, opp, bufsize, data);
 338                 break;
 339
 340         case OPROMPCI2NODE:
 341                 error = oprompci2node(argp, dp, opp, bufsize, data);
 342                 break;
 343
 344         case OPROMPATH2NODE:
 345                 error = oprompath2node(argp, dp, opp, bufsize, data);
 346                 break;
 347
 348         case OPROMGETBOOTARGS:
 349                 error = opromgetbootargs(argp, opp, bufsize);
 350                 break;
 351
 352         case OPROMU2P:
 353         case OPROMGETCONS:
 354         case OPROMGETFBNAME:
 355                 if (cnt++ < 10)
 356                         printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
 357                 error = -EINVAL;
 358                 break;
 359         default:
 360                 if (cnt++ < 10)
 361                         printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 362                 error = -EINVAL;
 363                 break;
 364         }
 365
 366         kfree(opp);
 367         return error;
 368 }
 369
 370 static struct device_node *get_node(phandle n, DATA *data)
 371 {
 372         struct device_node *dp = of_find_node_by_phandle(n);
 373
 374         if (dp)
 375                 data->lastnode = dp;
 376
 377         return dp;
 378 }
 379
 380 /* Copy in a whole string from userspace into kernelspace. */
 381 static int copyin_string(char __user *user, size_t len, char **ptr)
 382 {
 383         char *tmp;
 384
 385         if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
 386                 return -EINVAL;
 387
 388         tmp = kmalloc(len + 1, GFP_KERNEL);
 389         if (!tmp)
 390                 return -ENOMEM;
 391
 392         if (copy_from_user(tmp, user, len)) {
 393                 kfree(tmp);
 394                 return -EFAULT;
 395         }
 396
 397         tmp[len] = '\0';
 398
 399         *ptr = tmp;
 400
 401         return 0;
 402 }
 403
 404 /*
 405  *      NetBSD /dev/openprom ioctl calls.
 406  */
 407 static int opiocget(void __user *argp, DATA *data)
 408 {
 409         struct opiocdesc op;
 410         struct device_node *dp;
 411         char *str;
 412         const void *pval;
 413         int err, len;
 414
 415         if (copy_from_user(&op, argp, sizeof(op)))
 416                 return -EFAULT;
 417
 418         dp = get_node(op.op_nodeid, data);
 419
 420         err = copyin_string(op.op_name, op.op_namelen, &str);
 421         if (err)
 422                 return err;
 423
 424         pval = of_get_property(dp, str, &len);
 425         err = 0;
 426         if (!pval || len > op.op_buflen) {
 427                 err = -EINVAL;
 428         } else {
 429                 op.op_buflen = len;
 430                 if (copy_to_user(argp, &op, sizeof(op)) ||
 431                     copy_to_user(op.op_buf, pval, len))
 432                         err = -EFAULT;
 433         }
 434         kfree(str);
 435
 436         return err;
 437 }
 438
 439 static int opiocnextprop(void __user *argp, DATA *data)
 440 {
 441         struct opiocdesc op;
 442         struct device_node *dp;
 443         struct property *prop;
 444         char *str;
 445         int err, len;
 446
 447         if (copy_from_user(&op, argp, sizeof(op)))
 448                 return -EFAULT;
 449
 450         dp = get_node(op.op_nodeid, data);
 451         if (!dp)
 452                 return -EINVAL;
 453
 454         err = copyin_string(op.op_name, op.op_namelen, &str);
 455         if (err)
 456                 return err;
 457
 458         if (str[0] == '\0') {
 459                 prop = dp->properties;
 460         } else {
 461                 prop = of_find_property(dp, str, NULL);
 462                 if (prop)
 463                         prop = prop->next;
 464         }
 465         kfree(str);
 466
 467         if (!prop)
 468                 len = 0;
 469         else
 470                 len = prop->length;
 471
 472         if (len > op.op_buflen)
 473                 len = op.op_buflen;
 474
 475         if (copy_to_user(argp, &op, sizeof(op)))
 476                 return -EFAULT;
 477
 478         if (len &&
 479             copy_to_user(op.op_buf, prop->value, len))
 480                 return -EFAULT;
 481
 482         return 0;
 483 }
 484
 485 static int opiocset(void __user *argp, DATA *data)
 486 {
 487         struct opiocdesc op;
 488         struct device_node *dp;
 489         char *str, *tmp;
 490         int err;
 491
 492         if (copy_from_user(&op, argp, sizeof(op)))
 493                 return -EFAULT;
 494
 495         dp = get_node(op.op_nodeid, data);
 496         if (!dp)
 497                 return -EINVAL;
 498
 499         err = copyin_string(op.op_name, op.op_namelen, &str);
 500         if (err)
 501                 return err;
 502
 503         err = copyin_string(op.op_buf, op.op_buflen, &tmp);
 504         if (err) {
 505                 kfree(str);
 506                 return err;
 507         }
 508
 509         err = of_set_property(dp, str, tmp, op.op_buflen);
 510
 511         kfree(str);
 512         kfree(tmp);
 513
 514         return err;
 515 }
 516
 517 static int opiocgetnext(unsigned int cmd, void __user *argp)
 518 {
 519         struct device_node *dp;
 520         phandle nd;
 521
 522         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 523
 524         if (copy_from_user(&nd, argp, sizeof(phandle)))
 525                 return -EFAULT;
 526
 527         if (nd == 0) {
 528                 if (cmd != OPIOCGETNEXT)
 529                         return -EINVAL;
 530                 dp = of_find_node_by_path("/");
 531         } else {
 532                 dp = of_find_node_by_phandle(nd);
 533                 nd = 0;
 534                 if (dp) {
 535                         if (cmd == OPIOCGETNEXT)
 536                                 dp = dp->sibling;
 537                         else
 538                                 dp = dp->child;
 539                 }
 540         }
 541         if (dp)
 542                 nd = dp->node;
 543         if (copy_to_user(argp, &nd, sizeof(phandle)))
 544                 return -EFAULT;
 545
 546         return 0;
 547 }
 548
 549 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
 550                               unsigned int cmd, unsigned long arg)
 551 {
 552         DATA *data = (DATA *) file->private_data;
 553         void __user *argp = (void __user *)arg;
 554         int err;
 555
 556         switch (cmd) {
 557         case OPIOCGET:
 558                 err = opiocget(argp, data);
 559                 break;
 560
 561         case OPIOCNEXTPROP:
 562                 err = opiocnextprop(argp, data);
 563                 break;
 564
 565         case OPIOCSET:
 566                 err = opiocset(argp, data);
 567                 break;
 568
 569         case OPIOCGETOPTNODE:
 570                 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 571
 572                 if (copy_to_user(argp, &options_node->node, sizeof(phandle)))
 573                         return -EFAULT;
 574
 575                 return 0;
 576
 577         case OPIOCGETNEXT:
 578         case OPIOCGETCHILD:
 579                 err = opiocgetnext(cmd, argp);
 580                 break;
 581
 582         default:
 583                 return -EINVAL;
 584
 585         };
 586
 587         return err;
 588 }
 589
 590
 591 /*
 592  *      Handoff control to the correct ioctl handler.
 593  */
 594 static int openprom_ioctl(struct inode * inode, struct file * file,
 595                           unsigned int cmd, unsigned long arg)
 596 {
 597         DATA *data = (DATA *) file->private_data;
 598
 599         switch (cmd) {
 600         case OPROMGETOPT:
 601         case OPROMNXTOPT:
 602                 if ((file->f_mode & FMODE_READ) == 0)
 603                         return -EPERM;
 604                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 605                                             options_node);
 606
 607         case OPROMSETOPT:
 608         case OPROMSETOPT2:
 609                 if ((file->f_mode & FMODE_WRITE) == 0)
 610                         return -EPERM;
 611                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 612                                             options_node);
 613
 614         case OPROMNEXT:
 615         case OPROMCHILD:
 616         case OPROMGETPROP:
 617         case OPROMNXTPROP:
 618                 if ((file->f_mode & FMODE_READ) == 0)
 619                         return -EPERM;
 620                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 621                                             data->current_node);
 622
 623         case OPROMU2P:
 624         case OPROMGETCONS:
 625         case OPROMGETFBNAME:
 626         case OPROMGETBOOTARGS:
 627         case OPROMSETCUR:
 628         case OPROMPCI2NODE:
 629         case OPROMPATH2NODE:
 630                 if ((file->f_mode & FMODE_READ) == 0)
 631                         return -EPERM;
 632                 return openprom_sunos_ioctl(inode, file, cmd, arg, NULL);
 633
 634         case OPIOCGET:
 635         case OPIOCNEXTPROP:
 636         case OPIOCGETOPTNODE:
 637         case OPIOCGETNEXT:
 638         case OPIOCGETCHILD:
 639                 if ((file->f_mode & FMODE_READ) == 0)
 640                         return -EBADF;
 641                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 642
 643         case OPIOCSET:
 644                 if ((file->f_mode & FMODE_WRITE) == 0)
 645                         return -EBADF;
 646                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 647
 648         default:
 649                 return -EINVAL;
 650         };
 651 }
 652
 653 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
 654                 unsigned long arg)
 655 {
 656         long rval = -ENOTTY;
 657
 658         /*
 659          * SunOS/Solaris only, the NetBSD one's have embedded pointers in
 660          * the arg which we'd need to clean up...
 661          */
 662         switch (cmd) {
 663         case OPROMGETOPT:
 664         case OPROMSETOPT:
 665         case OPROMNXTOPT:
 666         case OPROMSETOPT2:
 667         case OPROMNEXT:
 668         case OPROMCHILD:
 669         case OPROMGETPROP:
 670         case OPROMNXTPROP:
 671         case OPROMU2P:
 672         case OPROMGETCONS:
 673         case OPROMGETFBNAME:
 674         case OPROMGETBOOTARGS:
 675         case OPROMSETCUR:
 676         case OPROMPCI2NODE:
 677         case OPROMPATH2NODE:
 678                 rval = openprom_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
 679                 break;
 680         }
 681
 682         return rval;
 683 }
 684
 685 static int openprom_open(struct inode * inode, struct file * file)
 686 {
 687         DATA *data;
 688
 689         data = kmalloc(sizeof(DATA), GFP_KERNEL);
 690         if (!data)
 691                 return -ENOMEM;
 692
 693         lock_kernel();
 694         data->current_node = of_find_node_by_path("/");
 695         data->lastnode = data->current_node;
 696         file->private_data = (void *) data;
 697         unlock_kernel();
 698
 699         return 0;
 700 }
 701
 702 static int openprom_release(struct inode * inode, struct file * file)
 703 {
 704         kfree(file->private_data);
 705         return 0;
 706 }
 707
 708 static const struct file_operations openprom_fops = {
 709         .owner =        THIS_MODULE,
 710         .llseek =       no_llseek,
 711         .ioctl =        openprom_ioctl,
 712         .compat_ioctl = openprom_compat_ioctl,
 713         .open =         openprom_open,
 714         .release =      openprom_release,
 715 };
 716
 717 static struct miscdevice openprom_dev = {
 718         .minor          = SUN_OPENPROM_MINOR,
 719         .name           = "openprom",
 720         .fops           = &openprom_fops,
 721 };
 722
 723 static int __init openprom_init(void)
 724 {
 725         struct device_node *dp;
 726         int err;
 727
 728         err = misc_register(&openprom_dev);
 729         if (err)
 730                 return err;
 731
 732         dp = of_find_node_by_path("/");
 733         dp = dp->child;
 734         while (dp) {
 735                 if (!strcmp(dp->name, "options"))
 736                         break;
 737                 dp = dp->sibling;
 738         }
 739         options_node = dp;
 740
 741         if (!options_node) {
 742                 misc_deregister(&openprom_dev);
 743                 return -EIO;
 744         }
 745
 746         return 0;
 747 }
 748
 749 static void __exit openprom_cleanup(void)
 750 {
 751         misc_deregister(&openprom_dev);
 752 }
 753
 754 module_init(openprom_init);
 755 module_exit(openprom_cleanup);